What My Brain Scan Revealed About the Science of Persuasion
(Bloomberg Businessweek) -- What exactly happens when we change our mind? Pursuing this question is how I found myself, one recent morning, lying in a fancy brain scanner known as an fMRI machine and watching cartoons at the Waisman Center at the University of Wisconsin at Madison. On the other side of a glass screen, a technician and two neuroscientists watched me—or, more accurately, watched my brain.
Cartoons notwithstanding, this is serious work. Understanding the neural basis of persuasion is a tantalizing prize for scientists and doctors, and obviously (and less nobly) businesses, politicians, and anyone else trying to get others to do their bidding. But the science is difficult enough to border on science fiction. Unlike regions of the brain that control motion, chiefly the motor cortex in the frontal lobe, the portions that control thought and persuasion are spread out. There’s no quadrant of the brain that lights up an fMRI machine when we’re thinking, “Huh, I guess you’re right.”
Still, pioneering neuroscientists are trying to decode persuasion. They want to isolate various types of high-level thinking—for example, can you separate neurons used in analysis from those used in memory?—and find out whether it’s even possible to identify the moment someone changes his mind. One idea that has gained currency: studying the effects of environment and interpersonal relationships on our openness to a particular message.
That’s why neuroscientists Chris Cascio and Matt Minich had me watch goofy video clips. Would I react less favorably to an image of tidy, meticulously sorted recycling bins if I had just watched the animated bear from the 2012 comedy Ted toss litter out a car window, or Stewie and Brian from the TV show Family Guy dock a small boat at an island composed of trash? Those images were meant to coax my brain into associating piles of garbage with a sense of normality.
Similarly, what would happen if I were shown text about ocean acidification after watching Marge Simpson hack down a forest, or pictures of people exercising after watching the characters from It’s Always Sunny in Philadelphia sit on a beach snacking on a booze-soaked ham? I won’t need to convince you that U.S. males selected these clips.
The experiment was run on 45 volunteers. (Excluding me: My readings won’t be included in the final results.) Findings are preliminary, and Cascio and Minich are preparing papers based on them.
The work focuses on the ventromedial prefrontal cortex and the ventral striatum, which appear to be important while we’re talked into something. These areas kick in when we decide whether something holds value and when we want to gain acceptance or approval from others.
Cascio and Minich, who work in the Communication, Brain and Behavior Lab at the university’s School of Journalism and Mass Communication, also check in on conflict detection regions such as the dorsal anterior cingulate cortex and the anterior insula to see what happens when a message is at odds with our beliefs. Minich, a doctoral student and avid runner, got interested in that question after years of pooh-poohing the idea of barefoot running—and then finding himself on a shoeless 8-mile jog after reading the book Born to Run. “What was that cognitive process?” he asks. (He’s back to running in shoes.)
As I lay in the scanner, taking in images and video clips on a computer screen, the researchers had a good idea of what areas would engage. They also cautioned against drawing conclusions based solely on my brain. “Single brains are messy,” says Cascio, the lab’s director. “We’re interested in what’s consistent across people.”
I watched the messages—mostly slides with text—and rated them with a clicker in my right hand on a scale of 1 to 4, 4 being most persuasive. Then I looked at cartoons, and then I watched and clicked through more messages. In my other hand was an alarm button in case of sudden claustrophobia. (As anyone who’s had an MRI is well aware, these machines are tight.)
Unlike in the movies, Cascio and Minich couldn’t see the results right away. They had to crunch the data over the next few days and then formulate brain maps. The data showed that when I watched some of the clips that made unhealthy or ungreen behavior seem normal, and then a persuasive message about the environment or health based on what I’d lose out on by, say, not exercising or recycling, the brain regions associated with value and acceptance showed less activity. But when they showed me messages that accentuated the positive, those regions lit up.
In other words: Persuasive messages are resonant even when they go against social norms, if they’re framed in the context of gains rather than losses. That’s important for knowing how to convince people when society is resistant to an idea. For example, an asset manager might base advertising on all the traveling, dining out, and home remodeling that could await investors aspiring for an early retirement, instead of dwelling on the potentially penurious future of those who don’t contribute to savings plans.
Is that manipulative? Yes, by definition. Creepy? It certainly could be, assuming neuroscientists ever deliver a practical model of persuasion. And they’re a long way off.
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